So I plan on moving to Tokyo in 2010

I know I still have a couple years till i move there,but i just had some questions...
I have been looking into apartments and japanese leasing customs..how much money should i have before moving there like an estimate what is the yearly cost of living there in the shibuya area?

That is a very expensive area to live in- probably you would need 500,000 to a million yen or more for set-up costs, including key money, deposit, rent in advance, agency fee, furniture etc.

There are so many variables though- furnished apartments are available, as are places without key money, and the size, age and exact location of the apartment has a huge effect on how much the rent (and therefore the key money, deposit etc.) will be.

What will you be doing in Japan, and what kind of apartment are you looking for? If you are willing to live 15- 20 minutes outside the Shibuya area by train you will save a lot on move-in and rent costs.

I agree living in any of the major areas in Central Tokyo where all the action happens (eg Shibuya) is going to cost more then if you lived in another area of Tokyo, or in a nearby prefecture, say 30mins - 2 hours commute is normal.